response directly? from yahoo

It appears that I´ve recieved a couple of automated responses to spam 
reports directly from yahoo. It is my understanding that any response would 
be send to spamcop, and then forwarded to me. As far as I remeber Yahoo was 
hosting spamvertized pages, and not actually the spammers. I´m not a 
proficient header interpreter, but I do see spamcop mentioned in them. I 
have pasted one of the headers below (without my own mail adress).
My question is:
 Is it true that spamhosts can reply directly (without some sort of hidden 
code)?.

Received: from appleton6.uni2.net (appleton6.uni2.net [129.142.244.20])
 by ting.uni2.net (8.12.6/8.12.6) with ESMTP id jA95uPLg032287
 for <xxxxxxx>; Wed, 9 Nov 2005 06:56:25 +0100
Received: from vmx1.spamcop.net (vmx1.spamcop.net [204.15.82.27])
 by appleton6.uni2.net (8.12.11/SQL-8.12.11-8/8.12.11) with ESMTP id 
jA95uNIN002853
 for <xxxxxxx>; Wed, 9 Nov 2005 06:56:24 +0100
Received: from sc-app1.ironport.com (HELO spamcop.net) (204.15.82.20)
  by vmx1.spamcop.net with SMTP; 08 Nov 2005 21:56:23 -0800
X-SpamCop-Reply-Ids: 1548721265
X-Spamcop-Return-Path: <[email protected]>
Received: from vmx2.spamcop.net (vmx2.spamcop.net [204.15.82.29])
 by sc-app1.soma.ironport.com (Postfix) with ESMTP id 389101A6DF
 for <[email protected]>; Tue,  8 Nov 2005 21:55:01 -0800 (PST)
Received: from mrout1.corp.ukl.yahoo.com (217.12.1.87)
  by vmx2.spamcop.net with ESMTP; 08 Nov 2005 21:55:00 -0800
Received: from kanasvr1.cc.ukl.yahoo.com (kanasvr1.cc.ukl.yahoo.com 
[217.12.1.199])
 by mrout1.corp.ukl.yahoo.com (8.13.4/8.13.4/y.out) with SMTP id 
jA95rrkC075842
 for <[email protected]>; Wed, 9 Nov 2005 05:54:00 GMT
DomainKey-Signature: a=rsa-sha1; s=serpent; d=yahoo-inc.com; c=nofws; q=dns;
 h=precedence:auto-submitted:date:to:subject:from:reply-to:
 mime-version:content-type:content-transfer-encoding:x-mailer;
 b=K5xtfUE427sQAPx9VUWZ7enMlRAV5L/FajPBEZD5n115otJWyEs3JRfbs+db/fLe
Message-Id: <[email protected]>